Xylorhiza cognata is a rare species of flowering plant in the family Asteraceae known by the common names Mecca-aster and Mecca woodyaster.[1] [2]
The shrub is endemic to the Colorado Desert within southern California, in Riverside County and Imperial County.[1] Most known populations are in the Mecca Hills and Indio Hills, located on the southeast side of the Coachella Valley and northeast of the Salton Sea.[1] [3] [4]
It grows in arid canyons and bajadas/washes, below 400m (1,300feet) within creosote bush scrub habitats of the Californian and northwestern Colorado Desert sub-region of the Sonoran Desert ecoregion of North America.[1]
Xylorhiza cognata is a woody subshrub with branching stems that may approach 1.5m (04.9feet) in height. They are hairy and glandular when new and lose their hairs with age. The leaves are lance-shaped to oval with smooth, toothed, or spiny 'holly-like' edges.[5]
The inflorescence is a solitary flower head with up to 30 or more pale lavender to pale violet rays surrounding a yellow central disk. Each petal may measure over 2 centimeters in length. The flowering period is January to June.[5]
The fruit is an achene which may be over a centimeter long, including its pappus of bristles.[5]
Xylorhiza cognata is a listed Endangered species on the California Native Plant Society Inventory of Rare and Endangered Plants. Threats to this species include recreational off-road and other vehicles, and potential property development projects.[3]